I am new to iPhone SDK. I have activated zombie and guard Malloc also. When I am playing with my application for 10 or 15 minutes, it crashes.
Now when my application crashed, console gives me some useful output, but I am not able to understand what it wants to say. So please help me.
Here is output of console :
GuardMalloc[GNG-4042]: Failed to VM allocate 400000 bytes
GuardMalloc[GNG-4042]: Explicitly trapping into debugger!!!
Now what should i do? Please help me. Thanking you.
Try profiling your code with the Instruments tool of Xcode to detect and fix memory leaks. Here is a good tutorial on using this tool: http://www.raywenderlich.com/2696/how-to-debug-memory-leaks-with-xcode-and-instruments-tutorial
Related
I am new here . Sorry if I this question is being repeated but I have a slightly different issue than the others.
My app crashes randomly after certain amount of time interval without any error logs or stack trace. I suspect it's an memory issue . I have the following questions :
1.) How to get stack trace (I have tried NSZombie enabled and NSUnacughtExcpetion handler) but didn't worked
2.) I get Memory warning frequently in my app. How do I confirm whether it's the prime suspect for the above issue? (I have used Leaks, my app crashes when it has just 4Mb usage so I am not quite sure whether memory leak is causing it my app to crash. I know certain application which take heap memory more than 4MB .)
3.) What is the upper limit for Memory leak for an application in iOS before app crashes ?
4.) Would ARC help me in this situation ?
Also, I have tried to debug issue using NSLog statements but since it crashes randomly , it would be hard for me to detect the root cause using this technique.
Any ideas would be or help would be really appreciated
My app crashes randomly after certain amount of time interval without any error logs or stack trace. I suspect it's an memory issue.
To confirm that it's a memory issue, sync your device with iTunes,and look in ~/Library/Logs/CrashReporter/MobileDevice/ for a files with LowMemory in their name. If you see (jettisoned) next to your app name, that confirms it was killed by iOS for using too much memory.
The only other way an app could exit without leaving a crash report is if it erroneously called exit().
For more information, see "Debugging Deployed iOS Apps", and "Understanding and Analyzing iOS Application Crash Reports".
Not sure but reading the registers might help.
First go to Exceptions tab and 'Add Exception Breakpoint' using the + at the bottom left corner.
Then when the app crashes click on "0 objc_exception_throw" under Thread 1
Finally in the console enter:
register read
(you should get a list of registers)
po $rax (normally the exception is in 'rax')
(you should see the exception output on the console)
Hope this helps.
That does sound like maybe the device is running low on memory and shutting you down. There's lots of threads on stackoverflow on debugging memory warnings.
This one talks a little about what to look for when using the Instruments tool.
Here is an explanation of how to get the memory warning level, and what the codes mean.
There is no fixed memory limit on iPhones. I've asked Apple support representatives this question, and they wouldn't give me a fixed answer (probably because the algorithm does not actually enforce any one hard limit for a 3rd-party app).
And, yes, ARC can be a wonderful thing. In your situation, you might have to rework a lot of code to make it all ARC-compliant, but ARC is definitely a useful feature, and can produce programs with fewer memory problems, with less work by the coders (leaving you more time to fix other problems!)
I recommend instrument
https://developer.apple.com/library/mac/#documentation/developertools/conceptual/InstrumentsUserGuide/AboutTracing/AboutTracing.html
In my case i closed all other apps and it started working normally, maybe it was a memory issue
I try to monitor the allocation through Instruments.
However, when I run to a point, sending some jabber msg, the Instruments stop working automatically.
I wonder how does it stop.
Is there any code in an app could stop the Instruments?
I have faced this problem too. The answer i got was: Instruments does stop if your memory usage is too high. Turn on Allocations, and see the memory usage. In my app, I was calling web services, which were downloading some heavy data, because of which my app's memory consumption would go unto like, 60-70 MB, (for an iPad app). This was causing instruments to crash.
So I had to put some memory fixes. I was able to reduce it to around 12 MB. And then Instruments resumed to work fine. Hope it helps.
It could also be as #Cory Kilger suggests and the app is crashing.
Try running it outside of instruments.
Good luck :)
so when i'm running my app using XCode and I can see that my app gets "program received signal 0".
However , the background thread are still running. why is that ?
Second, I can't seem to find any solution to this problem.
I assumed it might be memory leak, but I see nothing special using LEAKS (instrument).
When I run the app on the device(without XCode) and then try to see the device crash inside the organizer, most of the times there is no log (I guess maybe because the app is still running and only the main thread crashed) and while there is a log, my app function are only hex addresses without names.
What other options do I have to solve this issues ?
Thanks!!
I've found that sometimes these errors are caused by trying to access deallocated memory. One great tool to debug these issues is NSZombieEnabled. Here's a link to a good explanation of how to use NSZombieEnabled: CocoaDev: NSZombieEnabled
I have implemented pdf reader application for ipad.Its working fine in simulator.But its terminated in device with exit status 10.I done know whats happning.Please help me solve this problem.
Thanks in advance.
John,
Most likely it is a memory leak that is causing the app to get killed for consuming too much memory. Run the app with the Leaks tool (in the Run menu of XCode) and check how much memory gets allocated on load or during use.
Try it on the simulator first since you said it won't work on the device. Also, be sure you are releasing all objects you create after using them (but only the ones you create, not the ones Apple does).
A good reference guide to memory management: http://developer.apple.com/mac/library/documentation/cocoa/Conceptual/MemoryMgmt/MemoryMgmt.pdf
I have built my first game using Cocos2D. It worked fine on the simulator. But when it runs on the actual iPhone, it crashes. I don know why. Thought it was memory leaks, so i tried to detect, but no leaks found. I tried to increase and decrease frame rate, neither both succeeded. Anyone experienced please help me out. I am really stressed now. If anyone had the same issue please share with me your opinion.
Yours thanksfully.
I've run into similar issues (I also use Cocos, but I don't think this is Cocos specific). The best thing to do is plug-in your iPhone and watch the stacktrace when it crashes (or retrieve the stacktrace after the fact)
This happened to me a lot because the resources between the iPhone and the simulator were not in sync; in other words, some how resources would be available to the simulator (eg: images) but those same resources were not transferred to the iPhone for whatever reason. Sometimes, if I ran 'clean' on the simulator, I would observe the same issue.
It's extremely frustrating to debug these types of issues, but you'll get used to it.
I agree with Dominic - we definitely need more information to be able to help you - do you have the output from the console or the stack from the debugger?
Also, while memory leaks are a Bad Thing, they rarely lead to crashes directly. They will increase the amount of memory used by your app so if you're memory intensive then you might get a problem but they're not the first place I'd look to try to debug this.
Try running the app in Instruments and watch the memory usage graph - then not only can you see the total that your app is using but you can get an idea of which sections of your app use the most and can focus your efforts in reducing it.
Sam
Sorry, but you need to specify more details. How does it crash? What does the error log say? One thing you might look into is the amount of memory, your game consumes. If it uses more than 64 MB on the actual device, the OS will very likely just terminate it. In the simulator on the other hand, your app might use lots more memory without a problem.
I have found tools like Instruments and NSZombieEnabled to be very helpful in tracking down issues such as these.
Without more information, I would try the following steps:
Delete the app from the device and simulator (using the tap-and-hold technique to make your icons jiggle) and reinstall it. Sometimes a setting (or lack of a setting) in the user defaults will cause a crash, and those don't get wiped out unless you delete and re-run your app.
Also try the "simulate memory warning" option in the simulator and see if that gets it to crash.